Collaborative Research: Geochemical Signatures of Melt Segregation in Static vs. Dynamic Environments

9706047 Brearley关心地壳演化的地球科学家目前正在辩论熔体分离的速率，熔体运输途径的性质，以及构造环境的作用。特别是，重点放在岩浆化学，因为这些过程决定了提取的熔体与其源岩平衡的程度。因此，确定熔体分离的机制如何影响熔体化学，将大大提高我们的理解范围内观察到的组合物在深成花岗质岩石和地壳的演变一般。 在这个项目中，我们将实验测试的假设，熔体偏析的物理过程中留下了一个独特的化学签名，可以观察到和量化的重熔熔体。在静态和变形条件下进行的实验将使我们能够确定熔体组成时，1）迁移发生沿着熔体填充的裂纹在静态环境中，2）当迁移集中在沿着剪切带在动态环境中。总之，这些实验结果将提供一个重要的联系之间的构造环境，在深熔作用和岩浆成分的分离率。

9706047 Brearley Geoscientists concerned with crustal evolution are currently debating the rates of melt segregation, the nature of the pathways for melt transport, and the role of tectonic environment. In particular, focus has been placed on magma chemistry because these processes determine the extent to which the extracted melts are in equilibrium with their source rocks. Thus, determining how the mechanics of melt segregation influences melt chemistry would greatly enhance our understanding of the range in compositions observed in anatectic granitic terranes and of the evolution of the crust in general. In this project, we will experimentally test the hypothesis that the physical process of melt segregation leaves a distinct chemical signature that can be observed and quantified in anatectic melts. Experiments performed under both static and deformation conditions will allow us to determine melt compositions when 1) migration occurs along melt-filled cracks in quiescent environments and 2) when migration is focused along shear zones in dynamic environments. Together, these experimental results will provide an important link between tectonic environment, segregation rates active during anatexis and the magma compositions themselves.